ADC2 MT-002: What the Nyquist Criterion Means to Your Sampled Data System Design- -byWalt Kester INTRODUCTION A quick reading of Harry Nyquist's classic Bell System Technical Journal article of 1924 (Reference 1) does not reveal the true significance of the criterion which bears his name. Nyquist was working on the transmission of telegraph signals over a channel that was bandwidth limited. A thorough understanding of the modern interpretation of Nyquist's criterion is mandatory when dealing with sampled data systems. This tutorial explains in easy to understand terms how the Nyquist criterion applies to baseband sampling , undersampling, and oversampling applications. A block diagram of a typical real-time sampled data sy……